read Filter Method

The read filter method is called when a filter or
SAF calls the net_read function. Filters that are interested
in incoming data, that is, data sent from a client to the server implement
the read filter method.

Typically, the read method will attempt to obtain
data from the next filter by calling net_read(layer->lower, ...).
The read method may then modify the received data before
returning it to its caller.